<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>!important</title>
    <style type="text/css">
        h1 {
            color: red !important;
        }

        h1 {
            color: blue;
        }
    </style>
</head>
<body>
    <h1>为所欲为</h1>
</body>
</html>